Novel 3-indenecarboxylic acid-1-methine derivatives

ABSTRACT

A NOVEL CLASS OF 3-INDENECARBOXYLIC ACID-1-METHINE COMPOUNDS ARE DESCRIBED WHICH CAN BE USED TO DYE TEXTILE FIBERS OR TO PREPARE LIGHT SENSITIVE POLYMERS.

United States Patent ()fice 3,772,282

Patented Nov. 13, 1973 cyclic groups containing a hetero nitrogen atom;or 3,772,282 (3) an aromatic group represented by the structure: NOVEL3-INDENECARBOXYLIC ACID- l-METHINE DERIVATIVES R John A. Ford, Jr.,Rochester, N.Y., assignor to Eastman M 5 Kodak Company, Rochester, N.Y.5 I No Drawing. Continuation-impart of applications Ser. No. 4

846,852 and Ser. No. 846,958, both Aug. 1, 1969.

This application Sept. 14, 1970, Ser. No. 72,164

Int. Cl. C07c 69/74; C09b 23/00, 23/14 .s CL R 14 Claims where: Drepresents the atoms necessary to complete a benzene or a turanenucleus, i.e. D represents a -CH=CH, or an -O group; R and ABSTRACT OFTHE D SC R are each independently a hydrogen atom, a

A novel class of 3-indenecarboxylic acid-l-methine halogen atom 3 9alkyl group a lower alkoxy compounds are described which can be used todye textile 15 a lower dlfilkylammo group a hetero fibers or to preparelight sensitive polymers. cychc group contammg 5 6 the hetero nucleus atleast one of WhlCh 1s a nitrogen atom; and

This application is a continuation-in-part of US. Ser. 6 is al-methylidyne-3indencarboxylate group p NO. 846,952 filed Aug. 1, 1969,now US. Pat. 3,626,732 resented y the structural formula: issued Dec.14, 1971, and US. Ser. No. 846,958 filed Aug. 1, 1969, now US. Pat.3,694,411 issued Sept. 26,

-CH Th1s 1nvent1on relates to novel compounds. In a particular aspect,it relates to a novel class of methine dyes derived from3-indenecarboxylic acids which can be used to dye textile fibers andfabrics or which can be used to ('JooR1 prepare light sensitivepolymers.

The novel compounds of this invention are 3-indenecarboxylicacid-l-methine dyes which comprise a first and or a group represented bythe formula: second nucleus joined to each other by a methine linkage. RR The first nucleus is a 3-indenecarboxylic acid, or a 3- {CH C 8indenecarboxylic acid derivative joined to the methine linkage at the1-position of the indene nucleus, and the second nucleus is asubstituted benzene or naphthalene group, a heterocyclic groupcontaining 5 or 6 atoms in the hetero nucleus where at least one of theatoms is an oxygen or nitrogen atom, or a benzylidene or furfurylidenegroup substituted with a 1-indenylidene-3-carboxylic acid moiety, aheterocyclic dye nucleus, or a carboxy or carboxy ester group.

The 3-indenecarboxylic acid-l-methine dyes of this invention can berepresented by the structural formula where: n is 0 or 1; R and R are asdefined above; R is a hydrogen atom or a cyano group;

and R is a heterocyclic dye nucleus or a carboxy or carboXy ester groupof the formula -COOR where R is as defined above.

The lower alkyl groups represented by R R R and R typically have 1 to 8carbon atoms such as methyl, ethyl, propyl, butyl, amyl, hexyl,2-ethylhexyl, etc. The aryl group represented by R typically is abenzene group such as phenyl, tolyl, xylyl, etc. The lower alkoxy groupsrepresented by R R and R typically have 1 to 8 carbon atoms such asmethoxy, ethoxy, propoxy, butoxy, amyloxy, hexyloxy, heptyloxy,octyloxy, etc. The lower di- CH RB alkylamino groups represented by R,and R typically contain alkyl groups having 1 to 4 carbon atoms such asmethyl, ethyl, n-propyl, n-butyl, etc. Typical of the heterocyclic goupsrepresented by R, and R are pyrrolidino R1 (300m groups, piperidinogroups, morpholino groups, etc. Typical of the heterocyclic dye nucleirepresented by R are the quaternized salts of 5 or 6 memberedheterocyclic rings where: containing oxygen, sulfur, or nitrogen heteroatoms, or R is a hydrogen atom, a lower alkyl gro o an aryl combinationsof such hetero atoms, the ring optionally group; being fused to acarbocyclic ring system. Representative R is a hydrogen atom, a loweralkyl group, or a lower heterocyclic dye nuclei are thiazoline,thiazole, benzoxaalkoxy group; and zole, benzothiazole,fi-naphthothiazole, dimethylindo- R3 is one of the following moieties:6O lenine, quinoline and benzimidazole nuclei.

(1) a Substituted benzene or naphthalone group The 3-indenyl1denecarboxylic acld-l-methine dyes conbearing Such Substituents as nitrogroups, chloro veniently can be divided into five groups as followsgroups hydroxy groups, lower alkyl groups lower (1)l-(arylmethylene)-3-1ndencarboxylates having the alkoxy groups, or lowerdialkylamino groups; Structural formula:

(2) a heterocyclic group containing 5 or 6 atoms in the hetero nucleuswherein at least one of the R1 atoms is an oxygen or nitrogen atom, thehetero- X cyclic group optionally fused to a carbocyclic ring system andoptionally substituted with such substituents as lower alkyl groups,lower alkoxy R2 groups, aryl groups, or 5 or 6 membered hetero- OORI (2)l-(furfurylidene)-3-indenecarboxylates represented by the structuralformula:

CODE! (3) l-(benzylidene)-3-indenecarboxylates represented by thestructural formula:

R4 R5 R2 CH CH=OR1 (4) furylenedimethylidynel,l'-bis(3-indenecarboxylates) represented by the structural formula:

(5) phenylenedimethylidyne 1,1 bis(3-indenecarboxylates) represented bythe structural formula:

boon,

where n, R R R R R R and R are as defined above and R is an aromaticmoiety as defined above for R under (1) or (2).

Preferably, R is hydrogen or a lower alkyl group particularly methyl,ethyl or 2-ethylhexy1; R R R and R are hydrogen; when R, is aheterocyclic dye nucleus it preferably contains nitrogen oxygen orsulfur hetero atoms, or combinations of such hetero atoms in a 5- or6-membered ring which is optionally fused to a carbocyclic ring system.Particularly preferred heterocyclic dye nuclei are the thiazolium,benzothiazolium and naphthothiazolium dye salt.

Representative compounds of this invention include:arylenedimethylidyne-l, 1'-bis( 3-indenecarboxylates) such as:

dimethyl 1,3-phenylenedimethylidyne-1,1'-bis(3- indenecarboxylatediethyl 1,4-phenylenedimethylidyne-1,1'-bis(3-indenecarboxylate),

dimethyl4-dimethylamino-6-methyl-1,3-phenylenedimethylidyne-l,l-bis(3-indenecarboxylate),

dimethyl 4-dimethylamino-6-methyl-1,3-phenylenedimethylidyne-1,1-bis(4,7-dimethyl-3-indenecarboxylate),

dimethyl1,3-phenylenedimethylidyne-l,1'-bis(4,7-dimethyl-3-indenecarboxylate)dimethyl1,4-phenylenedimethylidyne-1,1'-bis(4,7-dimethyl-3-indenecarboxylate),

dibutyl 4-pyrr0lidino-1, 3-phenylenedimethylidyne-1,1'-

bis(3-indenecarboxylate),

dimethyl 4,6-dibutoxy-1,3-phenylenedimethylidyne-1,1'-

bis(3-indenecarboxylate),

diethyl 3-diethylamino-1,4 phenylenedimethylidyne-1,

1'-bis (4,7-diethoxy-3-indenecarboxylate) dimethyl2,S-furylenedimethylidyne-1,1' bis(3-indenecarboxylate),

dimethyl 2,4-furylenedimethylidyne-1,l'-bis(3-indenecarboxylate dimethyl2,5 -furylenedimethylidyne- 1 l '-bis(4,7-dimethyl-3-indenecarboxylate),

dimethyl4-dimethylamino-2,S-furylenedimethylidynel,l-bis(4,7-dimethyl-3-indenecarboxylate),and

dimethyl2,4-furylenedimethylidyne-1,1-bis(4,7-diethoxy-3-indenecarboxylate); and

1-arylmethylidyne-3-indenecarboxylates such as:

methyl 1-(4-methoxycarbonylbenzylidene)-3-indenecarboxylate,

methyl 1-[4-(2-methoxycarbonylvinyl) benzylidene]-3- indenecarboxylate,

methyl 1- [4- (2-methoxycarbonylvinyl benzylidene] -4,

7-dimethyl-3-indenecarboxylate,

ethyl 1-(3-ethoxycarbonylbenzylidene)-3-indenecarboxylate,

methyl 1-(3-methoxycarbonyl-4-dimethylamino-6-methy1-benzylidene)-3-indenecarboxylate,

ethyl 5-(3-methoxycarbonyl-l-indenylidenemethyl)furfurylidene-cyanoacetate,

methyl 1-[5-(Z-methoxycarbonylvinyl)furfurylidene1- 3-indenecarboxylate,

methyl 4,7-dimeth'yl-1-[5-(2-carbonylvinyl)furfurylidcue]-3-indenecarboxylate;

S-methoxycarbonyl-l-indenylidenemethylbenzoic acid,

3-( Z-ethylhexoxycarbonyl) -1-indenylidenemethylbenzoic acid,

3-cyano-1-indenylidenemethylbcnzoic acid,

3-methoxycarbonyl-1-indenylidenemethylcinnamic acid,

3- (Z-ethylhexoxycarbonyl) -l-indenylidenemethylcinnamic acid,

3-cyano-1-indenylidenemethylcinnamic acid,

p- [4,7-dimethy1-3-(2-ethylhexoxycarb0nyl) -1-idenylidenemethyl]-benzoic acid,

p-(4,7-dimethyl-3-methoxycarbonyl-l-idenylidenemethyl)cinnamic acid,

p-(5,6-dimethoxy-3-methoxycarbonyl-l-idenylidenemethyl)benzoic acid,

1-p-nitrobenzylidene-3-indenecarboxylic acid,

1-p-chl0robenzylidene-3-indenecarboxylic acid,

l-p-methoxybenzylidene-3-indenecarboxylic acid,

1-p-ethoxycarbonylbenzylidene-3-indenecarboxylic acid,

l-p-(2-ethylhexoxy)benzylidene-3-indenecarboxylic acid,

1- [5- 3-methoxycarbonyll-indenylidenemethyl)furfurylidene]-3-indenecarboxylic acid,

4,7-dimethyl-l-p-isopropylbenzylidene-Ii-indenecarboxylic acid,

4,7-diethyl-1-p-methoxybenzylidene-3-indenecarboxylic acid and5,6-dimethoxy-l-p-(2-ethylhexoxycarbony1)benzylidene-3-indenecarboxylicacid.

The compounds of this invention can be prepared by reacting a3-indenecarboxylic acid with an appropriate aromatic aldehyde. Thereaction is typically carried out in aromatic hydrocarbon solvents suchas toluene in the presence of an amine salt such as piperidine acetateat elevated temperatures. Alternatively, the reaction can be performedin the presence of an alkali metal alkoxide such as sodium or potassiummethoxide. The bis compounds can be prepared by using a bisaldehyde orby condensation of the indenccarboxylic acid with a monoaldehydefollowed by formylation of the resulting product to give an aldehydewhich is then further condensed with an additional amount of theindenecarboxylic acid, if a symmetrical compound is desired, or withanother reactant if a non-symmetrical compound is to be made.

Suitable aromatic aldehydes include benzaldehyde, substitutedbenzaldehydes such as p-nitrobenzaldehyde, p-

anisaldehyde, p-carboxybenzaldehydes, p-isopropylbenzaldehyde,o-chlorobenzaldehyde, 2,4 dichlorobenzaldehyde,p-diethylaminobenzaldehyde, 2,4-dichlorohydroxybenzaldehyde and 2,5dimethoxybenzaldehyde; naphthaldehyde, substituted naphthaldehydes suchas 2-hydroxy- 1 naphthaldehyde; p-formylcinnamic acid; bisaldehydes suchas terephthalaldehyde, isophthalaldehyde and 4-dimethylamino-6methylisophthalaldehyde; heterocyclic aldehydes such as 2 furaldehyde,pyrrole-2-carboxaldehyde, 2,5-dimethyl-1-(3-pyridyl) 3pyrrolecarboxaldehyde, indole-3-carboxaldehyde, and 2 methylene-1,3,3-trimethylindoline-w-carboxaldehyde, and the like.

Suitable indene carboxylic acids for use in this invention can beprepared by procedures known in the art such as are described in Crowell& Capps, Journal of the American Chemical Society 74, 4448 (1952).

The following examples further illustrate the invention.

EXAMPLE 1 3-indenecarboxylic acid To a solution of 43.4 g. (0.375 mole)of indene in 300 ml. of ether is added dropwise with stirring at -30 C.under nitrogen a solution of n-hutyllithium from 8.6 g. of lithium and68.5 g. of l-bromobutane (made by the procedure described in Gilman,Organic Reactions, vol. VI, p. 352). The mixture is stirred for minutesafter completion of the addition and then poured onto 400 g. of crushedDry Ice under 200 ml. of ether. The mixture is warmed to 5 C. on a steambath and extracted with two 250 ml. portions of water. Acidification ofthe combined aqueous portions, collection of the solid, andrecrystallization from 62.1 g. of benzene gives 41.2 g. (68.6 percent)of pale yellow crystals, M.P. 157-160 C.

Analysis.Calcd. for C H O (percent): C, 76.6; H, 6.38. Found (percent):C, 76.0; H, 6.6.

EXAMPLE 2 4,7-dimethyl-3-indenecarboxylic acid This compound is preparedas in Example 1 substituting an equivalent molar amount of 4,7dimethylidene for the indene.

EXAMPLE 3 2-ethylhexyl 3-indenecarboxylate A solution of 200 g. (1.25mole) or 3-indenecarboxylic acid, 2 liters of 2-ethyl-1-hexanol, and 5g. of p-toluenesulfonic acid is distilled slowly through a 6-inch columnpacked with A-inch glass helices for 5 hours, refluxed overnight, andthen distilled for 4 more hours. During this time the pot temperaturerises from 160 to 190 C.; and 26 ml. of water is distilled oif. Themixture is concentrated at the water pump and the residue dissolved in 1liter of petroleum ether (B.P. 35-60" C.) and allowed to standovernight. The filtered solution is washed with 500 m1. of water, 200ml. of saturated aqueous sodium bicarbonate, and again with 500 ml. ofwater. Drying over anhydrous sodium sulfate, concentration at the waterpump and fractionation of the residue gives 12.2 g. of forerun, B.P.l28l8l C. (1 mm.), 143 g. of pale yellow oil, B.P. 165-166 C. (1 mm.),r1 1.5195 and 64.5 g. B.P. 165-169 C. (1 mm.) n 1.5186. The yield of207.5 g. is 61.0 percent of the theoretical quantity.

Analysis.Ca1cd. for C H 0 (percent): C, 79.4; H, 8.83. Found (percent):C, 79.4; H, 8.4.

EXAMPLE 4 Methyl 4,7-dimethyl-3-indenecarboxylate A solution of 100 g.(0.532 mole) of 4,7-dimethyl-3- indenecarboxylic acid, 2 liters ofmethanol and 4 g. of ptoluenesulfonic acid is refluxed overnight,concentrated at the water pump, and then diluted with 500 ml. ofligroine (B.P. 35-60 C.) and chilled. After filtration from a trace ofsolid the solution is washed with 100 ml. of

6 water, ml. of 9 percent aqueous sodium bicarbonate, and then 100 ml.of water, dried with anhydrous sodium sulfate, and concentrated on asteam bath. Distillation of the residue gives 65.3 g. (60.8 percent) ofyellow oil, B.P. 165174 C. (10 mm), n 1.5506.

A nalysis.Calcd. for C I-1 0 (percent): C, 77.2; H, 6.9. Found(percent): C, 76.9; H, 6.9.

The following Examples 5-18 describe the preparation of compounds havingthe following generalized structure by the reaction of a3-indenecarboxylic acid with an appropriate aldehyde:

CH-Rn EXAMPLE 5 1-p-nitrobenzylidene-3-indenecarboxylic acid A mixtureof 40.0 g. (0.25 mole) of S-indeneacorboxylic acid, 36.3 g. (0.25 mole)of p-nitrobenzaldehyde, 250 ml. of toluene, 1 ml. of piperidine, and 1ml. of glacial acetic acid is refluxed for 2 hours with stirring andazeotropic removal of water and then cooled overnight in therefrigerator. The solid which crystallizes out of the reaction mixtureon cooling is collected, washed with toluene, and dried andrecrystallized from dioxane to give 41 g. (57 percent) of orangecrystals, M.P. 281-282 C.

EXAMPLE 6 1-p-methoxybenzylidene-3-indene carboxylic acid A solution of40 g. (0.25 mole) of 3-indenecarboxylic acid and 35 g. (0.26 mole) ofp-anisaldehyde in 320 ml. of methanol is treated with ml. of 30 percentpotassium hydroxide in methanol. The mixture is allowed to standovernight in a cold water bath and then is added to 500 ml. of water.Extraction of this mixture with ether, acidfication of the aqueousphase, collection of the solid washing with water, and drying at 60 C.gives 61 g. of product, M.P. 198200 C. Recrystallization fromchlorobenzene gives 41 g. (59 percent) of yellow crystals, M.P. 222 C.

EXAMPLE 7 2,5-dihydroxybenzylidene-3-indenecarboxylic acid This compoundis prepared using the procedure of Example 5 substituting an appropriateamount of 2,5- dihydroxybenzaldehyde for the p-nitro benzaldehyde.

EXAMPLE 8 4,7-dimethyl-1-p-isopropylbenzylidene-S-indenecarboxylic acidThe procedure of Example 5 is followed using 29.0 g.

Analysis.Calcd. for c,,H,,-o (percent): 0, 82.9; H, I

6.9. Found (percent): C, 82.8; H, 6.6.

EXAMPLE 9 5,6-dimethoxy-1-p-isopropylbenzylidene-3-indenecarboxylic acidThis compound is prepared as in Example 8 substituting an appropriateamount of 5,6-dimethoxy-3-indenecarboxylic acid for the4,7-dimethyl-S-indenecarboxylic acid.

7 EXAMPLE 10 1-[2,5-dimethyl-1-(3-pyridyl)-3-pyrrylmethylene]-3-indenecarboxylic acid A mixture of 25.0 g. (0.125 mole) of2,5-dimethyl-l- (3 pyridyl) 3 pyrrolecarboxaldehyde, 20.1 g. (0.125mole) of 3-indenecarboxylic acid, 250 ml. of toluene, 1 ml. ofpiperidine and 1 ml. of glacial acetic acid is refluxed for 4 hours withstirring and azeotropic removal of 2.3 ml. of water. The solid whichseparates upon cooling to room temperature is collected, washed withtoluene, and dried to give 39.0 g. of orange crystals, M.P. 260263 C.Recrystallization from 400 ml. of dioxane gives 21.6 g. (50.5%), M.P.255-256 C.

Analysis.Calcd. for C H N O (percent): C, 77.1; H, 5.26; N, 8.19. Found(percent): C, 76.8; H, 5.2; N, 8.1.

EXAMPLE 11 2-[2-(3-methoxycarbonylinden-1-ylidene)ethylidene]-1,3,3-trimethylindoline A solution of 17.4 g. (0.100 mole) of methyl3-indenecarboxylate, 20.1 g. (0.100 mole) of 2-methylene-l,3,3-trimethylindoline-w-carboxaldehyde, 150 ml. of toluene, 1 ml. ofpiperidine, and 1 ml. of glacial acetic acid is refluxed for 2 hourswith stirring and azeotropic removal of 2.0 ml. of water and then cooledto room temperature. The solid is collected, washed with toluene andwith ligroine (B.P. 6375 C.) and dried to give 20.7 g. of redvioletcrystals, M.P. 194-1945 C. Recrystallization from 200 ml. of toluenegives 17.9 g. (50.1%), M.P. 193- 194 C.

Analysis.-Calcd. for C H NO (percent): C, 80.6; H, 6.44; N, 3.92. Found(percent): C, 81.0; H, 6.6; N, 3.9.

EXAMPLES 12-17 Following the procedure of Example 5 and usingappropriate aldehydes and 3-indenecarboxylic acids, compounds areprepared wherein R R and R are as follows:

structural formula and of intermediates for use in preparing thecompounds.

A mixture of 32.0 g. (0.200 mole) of 3-indenecarboxylic acid, 19.2 g.(0.200 mole) of 2-furaldehyde, 200 ml. of toluene, 1 ml. of glacialacetic acid, and 1 ml. of piperidine is refluxed for 3 hours withstirring and azeotropic removal of 3.0 ml. of water. The solid whichseparates upon cooling to room temperature is recrystallized from 250ml. of dioxane to give 23.7 g. (49.8 percent) of orange crystals, M.P.246-254 C.

Analysis.Calcd. for C H O (percent): C, 75.6; H, 4.20. Found (percent):C, 75.3; H, 4.4.

Similar treatment of 29.2 g. (0.304 mole) of 2-furaldehyde with 52.8 g.(0.304 mole) of methyl 3-indenecarboxylate gives after 3recrystallizations from methanol 50.4 g. (65.8 percent) of orangecrystalline methyl l-furfurylidene-3-indenecarboxylate, M.P. 98.5100 C.

Analysis.Calcd. for C H O (percent): C, 76.2; H, 4.76. Found (percent):C, 75.9; H, 5.0.

EXAMPLE Methyl 1-(S-formylfurfurylidene)-3-indenecarboxylate To 100 m1.of dimethylformamide is added, with stirring and cooling to keep thetemperature below C., 7.7 g. (0.050 mole) of phosphoryl chloridefollowed by 12.6 g. (0.0500 mole) of methyl1-furfurylidene-3-indenecarboxylate. The mixture is stirred for 1 hourwithout heating and then for 1 hour at C., chilled in ice, and madebasic by slow addition of 2 N potassium hydroxide. The solid iscollected, washed with water, and

Example R1 2 9 13 -CH -H 15 H -H H0 15 -CH; 4,7-0113 N\ 17... CHzCHCaHs5,6-OCH The following Examples 19-26 illustrate the preparation ofcompounds having the following generalized recrystallized 4 times fromacetonitrile to give 4.6 g. (33 percent) or orange crystals, M.P.157158.5 C.

Analysis.Calcd. for C H 'O (percent): C, 72.7; H, 4.28. Found (percent):C, 72.9; H, 4.2.

When the reaction is run as described above in Example 20 with twice theamount of material, and the potassium hydroxide treatment is omitted, ared-brown crystalline solid separates after stirring overnight at roomtemperature. It is collected, washed with ether, and air dried to give25.4 g. which liquifies at 100 C., resolidifies, and melts at 151-155 C.This Vilsmeier product can be condensed with active methylene compoundsto give products identical with those fromI-(S-formylfurfurylidene)-3-indenecarboxylate and in some instances itmay be preferred since it is not necessary to purify the intermediates.

EXAMPLE 21 Ethyl -(3-1nethoxycarbonyl-l-indenylidenemethyl)furfurylidenecyanoacctate (A) From methyl1-(S-formylfurfurylidene)-3-indenecarboxylate:

A mixture of 14.1 g. (0.0504 mole) of methyl 1-(5-formylfurylidene)-3-indenecarboxylate, 5.7 g. (0.050 mole) of ethylcyanoacetate, 200 ml. of toluene, 1 ml. of piperidine, and 1 ml. ofglacial acetic acid is refluxed for 4 hours with stirring and azeotropicremoval of 1.9 ml. of water. The product which separates upon cooling toroom temperature is collected and recrystallized from 110 ml. of tolueneto give 13.1 g. (69.2 percent), M.P. 164-165 C.,

(log a) 272(4.24), 3336.63), 450(4.63), 475(4.62).

Analysis.Calcd. for C H NO (percent): C, 70.6; H, 4.53; N, 3.73. Found(percent): C, 70.5; H, 4.8; N, 3.7. (B) From the Vilsmeier Product fromExample 20:

To a solution of 2.5 g. (0.022 mole) of ethyl cyanoacetate in 100 ml. of3A alcohol is added 7.7 g. of the Vilsmeier product from Example 20 andthen 1 ml. of piperidine. The solution is refluxed for 4 hours and thenallowed to stand overnight at room temperature. The solid which hasseparated is collected and dried to give 6.7 g. of orange-browncrystals, M.P. and M.M.P. with A above 162-165 C. Recrystallization from50 ml. of toluene gives 5.8 g. (70 percent), M.P. 165-166.5 C.

EXAMPLE 22 2-{2- [2- 3-methoxycarbonyll-indentylidenemethyl -fur-5-yl]ethylidene}-3-ethylbenzothiazolium iodide ADCE max.

(log 6) 372 (4.66), 418 (4.70), 533 (4.70).

Analysis.Calcd. for C27H22INO3S (percent): C, 57.2; H, 3.87; I, 22.4; N,2.4. Found (percent): C, 57.8; H, 4.0; I, 21.4; N, 2.4.

EXAMPLES 23-26 Following the procedure of Example 22 and using suitableB-indenecarboxylates and aldehydes that are prepared compounds wherein RR R and R are as follows:

Example R; R; R1 Rs 11 23 H 4.7-CH3 COOH 0 24 H -H -H G) CH3 6 I9 25 H4.7-CH H COOH 1 26 ---H H H N 1 l 1 CH3 The following Examples 27-38illustrate the preparation of compounds having the following generalizedstruc- EXAMPLE 27 Methyl 1-p-carboxybenzylidene-3-indenecarboxylate Amixture of 10.7 g. (0.0713 mole) of p-carboxybenzaldehyde, 12.4 g.(0.0713 mole) methyl S-indenecarboxylate, 1 ml. of piperidine, 1 ml. ofglacial acetic acid, and ml. of toluene is refluxed for 2 hours withstirring and azeotropic removal of water. The mixture is cooledovernight in the refrigerator and the solid collected, Washedwith-toluene, and dried at 60 C. to give 19.0 g. of orange crystals,M.P. 250 C. Recrystallization from 350 ml. of dioxane gives 14.2 g.(65.0 percent), M.P. 274- 276 C.

Analysis.-Calcd. for C H O (percent): C, 74.5; H, 4.57. Found (percent):C, 74.8; H, 4.7.

EXAMPLE 28 Methyl 1-(p-methoxycarbonylbenzylidene)-3- indenecarboxylateA solution in 1500 ml. of methanol of the crude methyl 1(p-carboxybenzylidene)-3-indenecarboxylate prepared in Example 27 issaturated with hydrogen chloride gas and stirred overnight at reflux.The mixture is cooled, the solid collected by filtration, washed withmethanol, and dried to yield 36.9 g. of product, M.P. 152-6 C. The crudematerial is recrystallized twice from toluene to yield 33 g. of orangecrystals melting at 153156 C.

Analysis.-Calcd. for C H O (percent): C, 75.0; H, 5.0. Found (percent):C, 75.5; H, 5.4.

EXAMPLE 29 p-(4,7-dimethyl-3-methoxycarbonyll-indenylidenemethyl)cinnamic acid Amixture of 45.8 g. (0.227 mole) of 4,7-dimethyl-3-methoxycarbonylindene, 40.0 g. (0.227 mole) of p-formylcinnamic acid, 1ml. of glacial acetic acid, 1 ml. of piperidine, and 500 ml. of tolueneis refluxed for 2 hours in a flask fitted with a Dean-Stark moisturetrap, and then is allowed to stand for about 16 hours. A total of 2.8ml. of water is collected. The solid is collected by filtration andrecrystallized from 400 ml. of glacial acetic acid to yield 37.7 g. ofp-(4,7-dimethyl-3-methoxycarbonyl-l-indenylidenemethyl)cinnamic acidmelting at -188 C 1 1 EXAMPLE 30 Methylp-(4,7-dimethyl-3-methoxycarbonyl-l-indenylidenemethyl cinnamate Amixture of 16.8 g. (0.0466 mole) of the acid prepared in Example 29above, 500 ml. of methanol, 1 g. p-toluenesulfonic acid, and 2.5 g. of amixture of the above acid and its acid chloride is stirred at reflux for24 hours, gravity filtered, and allowed to cool to room temperature. Theprecipitated product is collected by filtration, washed 12 EXAMPLE 39Methyl 1- [5- 3-carboxy-l-indenylidenemethylfurfurylidene]-3-indenecarboxylate A mixture of 25.0 g. of the Vilsmeierproduct of Example 20, 11.6 g. (0.0728 mole) of 3-indenecarboxylic acid,and 200 ml. of methanol is warmed until solution results, treated with 1ml. of piperidine, and allowed to stand for 72 hours. The solid iscollected, washed with methanol, and recrystallized twice from dioxaneto give with methanol and dried to yield 10.7 g. of yellow solid 11.9 g.(39.8 percent) of brown crystals, M.P. 272.5- melting at 107-1 17 C. Asecond crop is obtained by con- 273.5 C. centrating the mother liquors.The combined crops are Analysis.Calcd. for C H O (percent): C, 75.2, H,recrystallized first from 500 ml. of cyclohexane, and then 4.38. Found(percent): C, 76.8; H, 4.6 from 250 ml. of ethanol to provide 8.8 g. ofproduct melting at 123-124 C. EXAMPLES 40-43 5 g g g' g i ig f 77'0; Bysubstituting appropriate 3-indenecarboxylic acids ound (percent) in theprocedure of Example 39, there are prepared com- EXAMPLE 31 pounds ofthis invention wherein R and R are as follows: 2 {2 [3 (3methoxycarbonylinden-1-yliden)-4-methyl- 20 6 diethylaminophenyl]vinyl}1 ethylbenzothiazolium Exam 19 R R iodide H Methyl 1-(4-d1ethylam1no 2methylbenzyl1dene)-3- -OH: 4,7CHa indenecarboxylate is prepared by theprocedure of Ex- CHB ample 27 using appropriate amounts of methyl3-indene- 43 CHzCHCzH -11 carboxylate and 4-diethylaminoZ-methylbenzaldehyde. 4H9 This product is formylated with phosphorylchloride in the presence of dimethyl formamide With stirring for onehour without heat following by stirring for one hour at 70 C. 30 Thefollowing Examples 44,51 illustrate the Prepam and the product isseparated by chilling II]. we and addition tion of compounds having thefollowing generalized 9 2 Potasslum hydrPxlde- Thls formylated (fompoundstructure wherein a suitable 3-indenecarboxylic acid is 1s collected,Washed with Water and recrystalhzed from reacted with an appropriatebisaldehyde acetonitrile after which it is converted to the dye productby reaction with 3-ethyl 2-methylbenzothiazolium iodide in methanol inthe presence of piperidine as a catalyst. R1 R2 EXAMPLES 32-38 OH OHUsing the procedure of the appropriate one of the k/ above examples andsuitable reactants, compounds of this 40 invention are prepared whereinR R R R R and R are as follows: COOR COOR Example R1 R1 R4 R5 R1 R3 71,

32 CH2-'CHCzH5 -H H H H -OOOH -H 5,6-OCH; -H H H G O 0 CH3 1 -0H: HN(CH3)1 H H CO0H 1 CH3 H 2H5 C1H5 COOH O H 4,7-011: -H --CN COOCHa 1 --HH H H --11 F o 1 N-CH;

ss...;..... 11 ]1 11 H H 0 1 The following Examples 39-43 illustrate theprepara- EXAMPLE 44 tion of compounds of this invention having thefollowing generalized f l Dimethyl4-d1methylamino-6-methyl-1,3-phenylenedimethylidyne-1,1'-bis(3-indenecarboxylate)A solution of 19.1 g. (0.100 mole) of 6-dimethyl- CH O CHamino-4-methylisophthaldehyde, 34.8 g. (0.200 mole) of methyl3-indenecarboxylate, 200 ml. of toluene, 1 ml. of X piperidine, and 1ml. of glacial acetic acid is refluxed for 2 hours with stirring andazeotropic removal of 3.6 ml. 0 B: @0031 of water. The orange-redsolution is cooled to room tem- 13 perature and poured into 1 liter ofligroine (B.P. 63-75 C.). The resulting two-phase liquid is allowed tostand for 4 hours with occasional manual stirring. The lower layer isseparated, boiled with 1 liter of acetonitrile and cooled overnight inthe refrigerator. The product is collected, washed with acetonitrile anddried to give 18.2 g. of

,orange-red crystals, M.P. 197200 C. Evaporation of the upper layer fromthe reaction mixture in the hood at room temperature gives a mixture ofbrown tar and orange-red crystals. Recrystallization using theacetonitrile filtrate from the first crop gives 15.1 g. of product, M.P.198.5201.5 C. The two crops are combined and recrystallized from 1.5 1.of acetonitrile to give 29.7 g. of orange-red crystals (59 percent) M.P.199201 C.

Analysis.Calcd. for C H 'NO (percent): C, 78.7; H, 5.76; N, 2.79. Found(percent): C, 78.9; H, 5.8; N, 3.0.

EXAMPLE 45 Dimethyl 1,3-phenylenedimethylidyne-1,l-bis-(4,7-dimethyl-3-indenecarboxylate) A solution of 44 g. (0.22 mole)methyl 4,7-dimethy1-3- indenecarboxylate, 13.4 g. (0.100 mole)isophthaldehyde and 200 ml. benzene is treated with 1 ml. of glacialacetic acid and 1 ml. piperidine and heated overnight under a moisturetrap to collect 3.5 ml. of water. The mixture is concentrated undervacuum to yield a yellow solid residue. The residue is recrystallizedonce from 350 ml. of ethyl acetate, and a second time from 200 ml. ofethyl acetate. Yield 37.6 g. of yellow solid melting at 136- 138.5 C.

Analysis.Calcd. for C H O (percent): C, 81.3; H, 5.98. Found (percent):C, 80.9; H, 6.2.

EXAMPLE 46 Preparation of dimethyl 4-dimethylamino-6-methyl 1,3-phenylenedimethylidyne 1,1 bis(4,7 dimethyl-3- indenecarboxylate) Amixture of 21.9 g. (0.108 mole) methyl 4,7-dimethyl-3-indenecarboxylate,10.8 g. (0.054 mole) 4-dimethylamino-6-methylisophthalaldehyde, 100 ml.benzene, 1 ml. glacial acetic acid and 1 ml. piperidine is refluxed forabout 16 hours, in a flask fitted with a moisture trap. The reactionmixture is cooled to room temperature and the orange-red product isseparated by filtration, washed with 200 ml. of ligroine, and dried toyield 29 g. The crude material is recrystallized 3 times from 150 ml.portions of toluene to provide 23 g. of product melting at 214- 216 C.

Analysis.-Calcd. for C H NO (percent): C, 79.5; H, 6.6; N, 2.5. Found(percent): C, 79.5; H, 6.7; N, 2.4.

EXAMPLE 47 Dimethyl 1,4-phenylenedimethylidyne-1,1-bis(3-indenecarboxylate) A mixture of 13.4 g. (0.100 mole) of terphthaldehyde,34.8 (0.200 mole) of methyl 3-indenecarboxylate, 400 m1. of toluene, 1ml. of piperidine, and 1 m1. of glacial acetic acid is refluxed for 3hours with stirring and azeotropic removal of 3.5 ml. of Water. Themixture is cooled to room temperature, and the solid is collected togive 40.5 g. of orange crystals, M.P. 223.5225 C. Recrystallization from800 ml. of dioxane gives 37.8 g. (84.8%), M.P. 224-225 C.

Analysis.-Calcd. for C H O (percent): C, 80.8; H, 4.93. Found (percent):C, 80.4; H, 5.1.

EXAMPLE 48 Dimethyl 1,3-phenylenedirnethylidyne-1,1-bis(3-indenecarboxylate) A mixture of 13.1 g. (0.0978 mole) ofisophthalaldehyde, 34.8 g. (0.200 mole) of methyl 3-indenecarboxylate,200 ml. of toluene, 1 ml. of glacial acetic acid, and 1 ml. ofpiperidine is reacted by the procedure described in Example 15 and thencooled overnight in the refrigerator.

14 The solid is collected and recrystallized first from acetonitrile andthen from toluene to give 26.3 g. (60.3%) of orange crystals, M.P.183-185 C.

Arzalysis.-Calcd. for C H O (percent): C, 80.8; H, 4.93. Found(percent): C, 80.6; H, 5.2.

EXAMPLES 49-51 Following the above procedure using appropriateindenecarboxylates and dialdehydes, compounds are prepared wherein R R Rand R are as follows:

Example R1 R2 R4 R5 49 H 4, 7-CH; CH3 CH3 50 -CHzCHC2H H -H H 51 CH3 5,6-0 OH; H -H An amount of 0.1 g. of the compound is dissolved in 10 cc.of 2-methoxyethanol. A small amount (3-5 cc.) of a 3% sodium ligninsulfonate aqueous solution is added, with stirring, and then the volumeof the bath is brought to 300 cc. with water. 3 cc. of an anionicsurfactant solvent carrier (Tanavol) is added to the bath and 10 gramsof a textile fabric made of poly(ethylene terephthalate) fibers isplaced in the bath and worked 10 minutes without heat. The dyeing iscarried out at the boil for one hour. The dyed fabric is removed fromthe dyebath and scoured for 20 minutes at C. in a solution containing 1g./l. neutral soap and 1 g./l. sodium carbonate. The fabric is thenrinsed, dried in an oven at C. and heat set (for the removal of residualcarrier) for 5 minutes at 350 C.

The compounds of the invention can also be applied to polyester textilematerials by the heat fixation technique described in US. Pat. 2,663,612and in the American Dye-Stuff Reporter, 42, 1 (1953). The followingprocedure describes how the 3-indenecarboxylic acid-1- methine compoundsof the invention can be applied to polyester materials by the heatfixation technique.

EXAMPLE 53 A mixture of 500 mg. of the dye compound, mg. of a sodiumlignosulfonate dispersing agent (Maraperse N), 150 mg. of a partiallydesulfonated sodium lignosulfonate (Maraperse CB), 0.5 ml. glycerin, and1.0 ml. of water is ground in a microsize container (an accessory for al-quart size Szegvari Attritor) for approximately 3.5 hours. EnoughAs-inch stainless steel balls are added to provide maximum grinding.When the grinding is complete, the entire contents are poured into abeaker and 100 ml. of water are used to wash the remaining dye pastefrom the micro-container. The dye paste is then heated slowly to 65 C.with continuous stirring. A thickener and penetrating mixture isprepared by mixing:

1 m1. of a complex diaryl sulfonate surfactant, (com pound 8-S),

3 ml. of a 3% solution of sodium N-methyl-N-oleoyltaurate,

8 ml. of a 25% solution of natural gums (Super-clear 80'N), andsuflicient water to bring the volume to 100 ml. The thickener andpenetrating mixture is added to the dye paste, the volume is adjusted to200 ml. and the mixture is agitated for 15 minutes. The dye mixture isthen filtered through folded cheesecloth to remove the stainless steelballs and it then is added to the reservoir of a Butterworth padderwhere it is heated to about 45- 60 C. 10 g. of a fabric of poly(ethyleneterephthalate) fibers and 10 g. of a fabric of 65/ 35 spun poly(ethyleneterephthalate)/cotton fibers are sewn together, end-toend, and paddedfor minutes of continuous cycling through the dye mixture and betweenthree rubber squeeze rollers of the padder. Dye mixture pick-up is about60% based on the weight of the fabrics. The padded fabrics are thendried at 95 C. and then heatfixed for 2 minutes at 215 C. in a forcedair oven. The dyed fabrics are scoured for 20 minutes at 6570 C. in asolution containing 0.2% sodium hydrosulfite, 0.2% sodium carbonate and1.7% of a 3% solution of sodium N methyl N oleoyltaurate and then dried.The dyed fabrics possess excellent brightness and exhibit outstandingfastness to light and sublimation when tested accord ing to theprocedures described in the 1966 edition of the Technical Manual of theAmerican Association of Textile Chemists and Colorists.

The heat fixation dyeing procedure described above can be varied by thesubstitution of other dispersing agents, surfactants, suspending agents,thickeners, etc. The temperature and time of the heat-fixation step canalso be varied.

Polymeric linear polyester materials of the terephthalate sold under thetrademarks Kodel, Dacron" and Terylene are illustrative of the lineararomatic polyester textile materials that can be dyed With the compoundsof our invention. Examples of linear polyester textile materials thatcan be dyed with the compounds of the invention are those prepared fromethylene glycol and dimethylterephthalate or from cyclohexanedimethanoland dimethylterephthalate. Polyesters prepared fromcyclohexanedimethanol and dimethylterephthalate are more particularlydescribed in U.S. Pat. 2,901,- 466. Poly(ethylene terephthalate)polyester fibers are described, for example, in U.S. Pat. 2,465,319. Thepolymeric linear polyester materials disclosed in U.S. Pats. 2,945,010,2,957,745, and 2,989,363, for example, can be dyed. The linear aromaticpolyester materials specifically named have a melting point of at least200 C. The poly(ethylene terephthalate) fibers which are dyed with thecompounds of the invention are manufactured from a melt of a polymerhaving an inherent viscosity of at least 0.35 and preferably, about 0.6.The inherent viscosity of the poly(1,4-cyclohexylenedimethyleneterephthalate) polymer is also at least 0.35. These inherent viscositiesare measured at 25 C. using 0.25 g. polymer per 100 ml. of solutionemploying a solvent mixture consisting of 60% phenol and 40%tetrachloroethane. The polyester fabrics, yarns, fibers and filamentsthat are dyed with the novel compounds of this invention can alsocontain minor amounts of other additives such as brighteners, pigments,delusterants, inhibitors, stabilizers, etc. Although the nonquaternizedcompounds of the invention are particularly suitable for dyeingpolyester textile materials, these compounds can also be used to dyeother synthetic, hydrophobic textile materials such as celluloseacetate, modified polypropylene, polyamide, modacrylic, etc. fibers.

The quaternized compounds of the invention can be used for dyeingacrylic and modacrylic polymer fibers, yarns and fabrics giving yellowshades when applied thereto by conventional'dye methods. Acrylic textilematerials are those which consist of at least 85% acrylonitrile andmodacrylic textile materials are those consisting of at least 35% byless than 85% acrylonitrile. The compounds of the invention also giveexcellent dyeings on acid-modified acrylic fibers described in U.S.Pats. 2,837,- 500, 2,837,501 and 3,043,811. The novel compounds can alsobe used to dye sulfonate modified polyester fibers such as are describedin U.S. Pat. 3,018,272. Examples of the textile materials that are dyedwith the compounds of 16 the invention are those sold under thetradenames Orlon, Orion 42, Verel, Acrilan, Dynel, and Creslan.

Such textile materials dyed by the quaternized compounds of theinvention are characterized by containing at least about 35% combinedacrylonitrile units and up to about 95% acrylonitrile units, andmodified, for example, by 655% of vinyl pyridine units as described inU.S. Pats. 2,990,393 (Re. 25,533) and 3,014,008 (Re. 25,539) or modifiedby 655% of vinylpyrrolidone units, for example, as described by U.S.Pat. 2,970,783, or modified with 655% acrylic ester or acrylamide unitsas described in US. Pats. 2,879,253, 2,879,254 and 2,838,470. Similaramounts of the other polymeric modifiers mentioned above are alsouseful. A preferred group of the copolymers readily dyeable with thequaternized dyes of the invention are the modacrylic polymers such asdescribed in U.S. Pat. 2,831,826 composed of a mixture of (A) 7095% byWeight of a copolymer of from 30 to 65% by weight of vinylidene chlorideor vinyl chloride and 7035% by weight of acrylonitrile, and (B) 305% byweight of a second polymer from the group consisting of (1) homopolymersof acrylamidic monomers of the formula wherein R is selected from thegroup consisting of hydrogen and methyl, and R and 12 are selected fromthe group consisting of hydrogen and alkyl groups of 1-6 carbon atoms,(2) copolymers consisting of at least two of said acrylamidic monomers,and (3) copolymers consisting of at least 50% by weight of at least oneof said acrylamidic monomers and not more than 50% by weight of apolymerizable monovinyl pyridine monomer.

Another type of modacrylic polymer that can be dyed with the quaternizedcompounds of the invention is an acetone soluble mixture of (A) 7095% byweight of a copolymer of 3065% by weight of vinylidene chloride and7035% by weight of acrylonitrile and (B) 305% by weight of an acrylamidehomopolymer having the above formula wherein R R and R are as describedabove. Specific polymers of that type contain 7095% by weight of (A) acopolymer of from 3065% by weight of vinylidene chloride and 7035% byweight of acrylonitrile and (B) 305% by weight of a lowerN-alkylacrylarnide polymer such as poly-N-methylacrylamide,poly-N-isopropylacrylamide and poly-N-tertiarybutylacrylamide.

The following example illustrates one way in which the compounds of theinevntion can be used to dye acrylonitrile polymer textile material.

EXAMPLE 54 The dye (0.1 g.) is dissolved by warming in 5 cc. of2-methoxyethanol. A 2% aqueous solution of a nonionic surfactant, suchas Igepal CA (a polymerized ethylene oxide-alkylphenol condensationproduct), is added slowly until a fine emulsion is obtained and then thedye mixture is brought to a volume of 200 cc. with warm water. Five cc.of a 5% aqueous solution of formic acid or acetic acid are added andthen 10 grams of fabric made from an acrylic fiber is entered and, inthe case of Orlon 42 acrylic textile material, the dyeing is carried outat the boil for one hour. In the case of materials made of Verelmodacrylic fiber the dye-bath temperature should not exceed C. in orderto avoid damage to the fiber. The dyed material is then washed well withwater and dried.

The invention has been described in detail with particular reference topreferred embodiments thereof, but it will be understood that variationsand modifications can be effected within the spirit and scope of theinvention.

17 What is claimed is: 1. A 3-indenecarboxylic acid-l-methine compoundhaving the structural formula where I R is selected from the groupconsisting of a hydrogen atom, a lower alkyl group and a phenyl or loweralkyl substituted phenyl group;

R is selected from the group consisting of a hydrogen atom, a loweralkyl group and a lower alkoxy group; and

R is an aromatic moiety selected from the group consisting of (1) anaphthalene group substituted with substituents selected from the groupconsisting of nitro groups, chloro groups, hydroxy groups, lower alkylgroups, lower alkoxy groups and lower dialkylamino groups;

(2) a heterocyclic group selected from the group consisting of pyrryl,pyridyl, indolinyl, and furfuryl; and

(3) an aromatic group represented by the structure where D is selectedfrom the group consisting of o and CH=OH.

R and R are each selected from the group consisting of a hydrogen atom,a halogen atom, a

lower alkyl group, a lower alkoxy group, a lower dialkylamino groups, aheterocyclic group selected from the group consisting of pyrrolidinogroups, piperidino groups and morpholino groups; R is selected from thegroup consisting of a l-methylidyne-3-indinecarboxylate grouprepresented by the structural formula --CH I where R and R are asdefined above, and a group represented by the formula +011: cna n,

where n is 0 or 1; R is a hydrogen atom or a cyano group, and R is aheterocyclic dye nucleus selected from the group consisting ofthiazoline, thiazole, benzoxazole, benzothiazole, fl-naphthothiazole,dimethylindolenine, quinoline and benzimidazole nuclei or a carboxyl orcarboxy ester group of the formula COOR where R 1s as defined above.

2. A 1-arylmethylene-3-indenecarboxylate having the structural formulaCHI-Ru wherein R is selected from the group consisting of a hydrogenstructural formula fi-CH=C B7B; C

( ZOOR wherein R is selected from the group consisting of a hydrogenatom, a lower alkyl group and phenyl or lower alkyl substituted phenylgroup;

R is selected from the group consisting of a hydrogen atom, a loweralkyl group and a lower alkoxy group;

R is selected from the group consisting of a hydrogen atom, a halogenatom, a lower alkyl group, a lower alkoxy group, a lower dialkylaminogroup and a heterocyclic group selected from the group consisting ofpyrrolidino, piperidino and morpholino;

R is a hydrogen atom or a cyano group and R is a heterocyclic dyenucleus selected from the group consisting of thiazoline, thiazole,benzoxazole, benzothiazole, B-naphthothiazole, dimethylindolenine,quinoline and benzimidazole nuclei or a carboxyl or carboxy ester groupof the formula COOR where R is as defined above. 4. A l-benzylidene3-indenecarboxylate having the structural formula where n=0 or 1 R isselected from the group consisting of a hydrogen atom, a lower alkylgroup and phenyl or lower alkyl substituted phenyl group;

R is selected from the group consisting of a hydrogen atom, a loweralkyl group and a lower alkoxy group;

R and R are as defined above;

R is a hydrogen atom or a cyano group; and

R is a heterocyclic dye nucleus selected from the group consisting ofthiazoline, thiazole, benzoxazole, benzothiazole, fl-naphthothiazole,dimethylindolenine, quinoline and benzimidazole nuclei or a carboxy orcarboxy ester group of the formula COOR where R is as defined above. 5.A furylenedimethylidyne-l,l'-bis(3 indene-carboxylate) having thestructural formula COOBI where CH CH where R is selected from the groupconsisting of a hydrogen atom, a lower alkyl group and phenyl or loweralkyl substituted phenyl group;

R is selected from the group consisting of a hydrogen atom, a loweralkyl group and a lower alkoxy group;

and R and R are selected from the group consisting of a hydrogen atom, ahalogen atom, a lower alkyl group, a

lower alkoXy group, a lower dialkylamino group and a heterocyclic groupselected from the group consisting of pyrrolidino, piperidino andmorpholino.

7. A compound as defined in claim 3 wherein R is a lower alkyl group, RR and R are hydrogen atoms; and R is a heterocyclic dye nucleus selectedfrom the group consisting of thiazoline, thiazole, benzoxazole,benzothiazole, fi-naphthothiazole, dimethylindoline, quinoline andbenzimidazole nuclei or a carboxy or carboxy ester group of the formulaCOOR where R is as defined above.

8. A compound as defined in claim 4 wherein R is a lower alkyl group, RR R and R are hydrogen atoms and R is a heterocyclic dye nucleusselected from the group consisting of thiazoline, thiazole, benzoxazole,benzothiazole, B-naphthothiazole, dimethylindolenine, quinoline andbenzimidazole nuclei or a carboxy or carboxy ester group of the formulaCOOR- where R is as defined above.

9. A compound as defined in claim 5 wherein R s a lower alkyl group, andR and R are halogen atoms.

10. A compound as defined in claim 6 wherein R is a lower alkyl groupand R R and R are hydrogen atoms.

11. Dimethyl 1,4-phenylenedimethylidine-l,l'-bis(3-indenecarboxylate).

12. Dimethyl 1,3-phenylenedimethylidine-1,1-bis(3-indenecarboxylate) 13.2 (2 [2 (3 methoxycarbonyl l indenylidenemethyl) fur 5 yl]ethylidene) 3ethylbenzothiazolium iodide.

14. Ethyl 5-(3 methoxycarbonyl-l-indenylidenemethyl)furfurylidenecyanoacetate.

References Cited UNITED STATES PATENTS 3,627,732 12/1971 Ford et a1 260U OTHER REFERENCES Wislicenus et al.: Annalen der Chemie, vol. 436, pp.9, 16-17, 25-26 and 28-29 (1924).

JOHN D. RANDOLPH, Primary Examiner US. Cl. X.R.

8--54.2, 177 R, 178 R, 179; 260240 D, 468 R, 515 R, 520

